Double primary synchronous and metachronous cancer of the larynx and hypopharynx with dissimilar histology. Five case reports and review of the literature.

Five cases of double primary synchronous and metachronous cancers of the larynx and hypopharynx with dissimilar histology encountered at the Section of Pathology of the Department of Otolaryngology of Padua University from 1966 through 1979 are reported. The pathogenesis of these double primary malignancies is discussed, and in particular stress is laid on the perhaps not purely coincidental association of squamous cell and oat cell carcinoma of the larynx and hypopharynx. Furthermore, a thorough review of the literature is made on the reported cases of two primary simultaneous or metachronous malignancies of the larynx and hypopharynx of different histological type.